According to Tertullian (c. 155 - c.240 A.D.), early Christians did not have a single best prayer position they used. They, instead, favored several positions such as standing, sometimes with their heads bowed, with their arms extended at their sides (like the shape of a cross) or with them raised toward heaven. They were also inclined to kneel or prostrate themselves when making their petitions to God. The striking of the chest while in prayer to the Eternal (as we find in Jesus' parable of the Pharisee and the Tax collector in Luke 18:9 - 14) was also sometimes practiced.
After arriving at the garden, located at the foot of the Mount of Olives, the Lord seems to have first offered a prayer while kneeling (Luke 22:41). He soon, however, switched to a position of kneeling and bowing his head such that it touched the ground (Matthew 26:39) while he sought the Father's will regarding what awaited him. Other individuals in Scripture are also recorded as crying out to God while kneeling and placing their face on the ground (Numbers 16:22, Joshua 5:15, 1Chronicles 21:16).
King Solomon prayed while on his knees with his arms outstretched toward God (1Kings 8:54). In fact, hands were many times lifted up (either while kneeling or standing), and sometimes spread out, during prayer (Psalm 28:2, 1Kings 8:54, Lamentations 2:19, Isaiah 1:15, Ezra 9:5 - 6, 1Timothy 2:8, etc.).
Prayer was also, many times, given while standing up (1Samuel 1:26, Judges 16:25 - 28). Abraham, while talking directly with Jesus Christ regarding the fate of Sodom and Gomorrah, stood (Genesis 18:22 - 33). This position was especially common among Jews in New Testament times (see Matthew 6:5, Mark 11:25, Luke 18:11, 13, etc.). Even in modern times, Jews frequently stand while they pray and bemoan the destruction of Jerusalem's temple at the place known as the Wailing Wall.
The Bible even records one instance where King David sat down to talk to the Lord. He did so in order to praise Him regarding the promise to make his descendants into a perpetual ruling dynasty over Israel (1Chronicles 17:16). Jonah, after he was swallowed by a great fish, likely prayed when he was in some sort of fetal position in the beast's belly (Jonah 2:1).
Recipe for the perfect prayer
What constitutes an ideal or best prayer that can be offered to God? As this article has shown, although it is always acceptable to kneel, many other physical positions can be utilized. The Bible does list, however, many definitive characteristics of the "ideal" petition made to our heavenly Father. For example, it should be simple (Matthew 6:7), made in humility (2Chronicles 7:14, Psalm 10:17, Luke 18:13 - 14) and offered in sincerity (Psalm 17:1, 145:18).
Additionally, in prayer, we should be persistent (Luke 18:8 - 9, 18:1 - 7), bold (Hebrews 4:16) and have faith that the Eternal not only hears us but also rewards those who diligently seek him (Hebrews 11:6). We should make our petitions known in accordance to God's will (1John 5:14) and should be living a life that obeys his commandments (1John 3:22). Our hearts should also be ready and willing to forgive every person of every sin they committed against us (Matthew 6:12 - 15). Ultimately, the best prayer position is anything you find comfortable and relaxing.